Dwelling construction system

ABSTRACT

In a dwelling construction system, a multi-story, multi-family building comprises prestressed concrete pallets which are supported between load bearing walls to form the floors and the ceilings of individual dwellings. Each dwelling includes a service core comprising an enclosure formed on one of the pallets and complete mechanicals for the dwelling. The service cores are fabricated by mass production techniques and are subsequently transported to the building site for installation. In some instances the service core comprises a complete dwelling, in which case the enclosure of the service core may form the exterior walls and the roof of the dwelling.

Elite Staes [191 Il 3,92,287 Livingston Sept, 2, 1975 [5 DWELLING CONSTRUCTION SYSTEM OTHER PUBUICATIONS [75] Inventor: Johnston R. Livingston, Denver,

C010 Architectural Catalog File, Sweets Catalog Service 1962 2h/li, 2 and 3, 2h/sc, 2 and 3. [73] Assignee: Marcor Housing Systems, pp pp Incorporated, Denver, Colo.

Primary Examiner.Iohn E. Murtagh [22] Flled' May 1973 Attorney, Agent, or Firm-Hubbard, Thurman, Turner [21] Appl. No.: 361,805 & Tucker Related US. Application Data [60] Division of Ser. No. 230,803, March 1, 1972, Pat. TRQ

No. 3,800,493, which is a continuation-in-part of Ser. [57] ABS July 1971 abandoned In a dwelling construction system, a multi-story, multifamily building comprises prestressed concrete pallets [52] lU.S.Cl.2 which are supponed between load bearing Walls to if: 79 35 form the floors and the ceilings of individual dwell- [5 1 d 0 Bare 3 6 ings. Each dwelling includes a service core comprising an enclosure formed on one of the pallets and complete mechanicals for the dwelling. The service cores [56] References Cned are fabricated by mass production techniques and are UNITED STATES PATENTS subsequently transported to the building site for instal- 3,l62,863 12/1964 Wokas 52/34 lation. In some instances the service core comprises a 3,292,327 1 1 66 an D r L ly--- 52/79 complete dwelling, in which case the enclosure of the 3,416,273 12/1968 s 52/745 service core may form the exterior walls and the roof 3,616,592 12/l97l Rothman 52/745 of the dwelling. 3,762,115 10/1973 McCaul 52/79 FOREIGN PATENTS OR APPLICATIONS 16 Claims, 28 Drawing Figures PATENTEUSEP 2975 SHEET PATENTEI] SEP 2 5975 v SHEET PATENTEDSEP 2mm SHEET .w/mm

WW on PATENTED SEP 2 I975 SHEET PATENTED SEP. 2 I975 SHEET Illlllllllllllllllllllllli mmum PAT

ENTED SEP 2&975

SHEET PATENTEDSEP 2l975 33029287 SHEET 9 PATENTEB EP 2197s SHEET m 4 v... r \rm\w v\(\ IX) a. .w 2 3 o n w 6 0. 9 O w 4. A m r 2 (Y2 a 4 N N w m V. 4 O 4 I 4 n a P" w W 4 M a 1 4 d PATENTEU 35? 21975 SHEET PATENTEDSEP zirs DWELLING CONSTRUCTION SYSTEM RELATED APPLICATION This is a division of application Ser. No. 230,803, filed Mar. 1, 1972, now U.S. Pat. No. 3,800,493.

Application Ser. No. 230,803 is a continuation-inpart of co-pending application Ser. No. 166,545, Filed July 27, 1971, now abandoned.

BACKGROUND AND SUMMARY OF THE INVENTION This invention relates t dwelling construction systems, and more particularly relates to a system for fabricating a wide range of dwelling types using production line techniques.

Very substantial sums of money have been expended over the last decade or two to develop building systems which use production line techniques in the construction of both single family and milti-family dwellings. The basic considerations fueling this activity are rapidly increasing labor costs of tradesmen, and the hope that use of production line manufacturing procedures would reduce or eliminate the need for the highly skilled labor of tradesmen as well as provide other cost savings.

This type of construction is particularly promising in the case of dwellings to be erected at remote or relatively inaccessible building sites where labor and materials are not readily accessible.

To date the most successful adaptation of production line techniques to dwelling construction has been in the mobile home industry. As is well known, the fabrication ofa trailer house, including the installation ofmechanicals such as kitchen, bathroom, and temperature control facilities, is typically carried out to completion at a factory. By this means the labor required to install such a dwelling at a particular site is reduced to an absolute minimum.

A different but related method of adapting mass production to dwelling construction comprises sectionalized houses. Typically half or quarter house sections are fabricated at a factory using conventional building materials and techniques and aretransported to a construction site by truck. At the site the sections are positioned adjacent one another and are joined to form a completed house.

Multi-family dwelling units have also been constructed using production line techniques. By way of example, one construction system that has been used heretofore involves the fabrication of box-like modules each including a floor, walls and a ceiling which are interconnected to form a structurally integral and trans- A portable unit. The finishing of the modules, including the installation of mechanicals, is completed at a factory. Thereafter the modules are transported to a construction site and are stacked in various configurations to form dwelling units. In this case, the interrelationship of the floor, walls and ceilings of each module cooperates to provide the structural integrity and load bearing capacity necessary to permit the modules to be transported and handled. This type of system has the inherent disadvantage of greatly limiting flexibility of design, and also results in duplicate wall structures.

Although the modular building systems heretofore used have provided some cost reduction, the systems are inherently inflexible and greatly limit the architectural design and livability of the structures. In general,

the greater the modularization of the system to achieve reduced costs, the more inflexible the system is to design change, the smaller the rooms, and the more unlivable the dwelling.

Another trend in the construction industry involves the use of prestressed concrete structural components. Thus, structures such as bridges, parking garages, warehouses and the like are presently being fabricated from various prestressed components including load bearing and non-load bearing walls, columns, beams, and floor and roof decks. Heretofore prestressed members have been used solely as structural. elements. This practice necessitates the use of labor at the construction site to perform such tasks as erecting interior partitions, installing mechanicals, etc.

The present invention comprises a novel dwelling construction system which incorporates many of the advantages that are characteristic of prior art modular construction systems while eliminating substantially all of the disadvantages that have long been associated with such systems. In accordance with the broader aspects of the invention, a service core is substantially completely fabricated on an assembly line using mass production techniques. The service core is formed on a prestressed concrete pallet which is also fabricated at a plant site using automated equipment for greatest economy. The service core includes a mechanical enclosure which may be fabricated from conventional drywall building materials of the type used in building houses, and similar buildings. The mechanical enclosure may include complete mechanicals for at least one dwelling, i.e., complete kitchen facilities, complete bathroom facilities, complete temperature control equipment, and electrical systems including telephone and television wiring.

Upon completion, each service core is transported to a dwelling site. The concrete pallet provides the only structural integrity required, thus giving total flexibility I in the design of the enclosures. In some instances the service core may comprise an entire dwelling. More often, however, each service core is employed in conjunction with additional prestressed concrete pallets to form a relatively large dwelling. In the latter case the pallets extend between and are supported by prestressed concrete load bearing walls to provide a clear span of substantial length. Additional combinations of service cores and pallets may also be supported on the load bearing walls to form garden apartments, high rise apartments, and the like.

In accordance with more specific aspects of the invention, the prestressed concrete pallets used in the service cores and used in conjunction with the service cores to construct dwellings each comprise a relatively thin deck, a plurality of integrally formed beams depending from the deck, and pretensioned members ex tending through the beams to prestress and maintain the concrete of the beams in compression such that the beams are adapted to span a substantial distance between two spaced load bearing points and still support large static and live loads on the deck. The deck may terminate at the load bearing points, in which case the deck is entirely enclosed by the load bearing walls. On the other hand, the beams may be cantilevered substantially beyond either of the load bearing points to support a deck portion located outside the load bearing walls to provide a balcony, an entry corridor, etc.

In the use of the present invention to construct a multi-family dwelling such as a garden apartment, a pair of load bearing wall panels are initially erected at points spaced in accordance with the positioning of the support points of the beams of the concrete pallets. After the load bearing wall panels are in place, a service core and then one or more additional pallets are set in place on the load bearing wall panels to form the floor of a first story dwelling. In the case of the first floor dwell ing, the beams of the pallets may rest on members projecting inwardly from the load bearing wall panels.

Non-load bearing shear wall panels interconnect the load bearing wall panels and serve the dual functions of enclosing the dwelling and maintaining the load bearing wall panels erect.

A service core and then additional pallets which form the ceiling of the first floor dwelling and the floor for a second story dwelling are set in place on the top edges of the load bearing walls of the first floor unit. The beams of the pallets of the second dwelling are preferably received in notches formed in the upper ends of load bearing wall panels that enclose the lowermost dwelling. Also, the decks of the pallets forming the floor of the second dwelling preferably either end at or are interrupted at points corresponding to the positioning of the load bearing wall panels. This permits mounting a second pair of load bearing wall panels directly on the first pair of load bearing wall panels to form the walls for the second floor dwelling.

When the second set of pallets are in place, a second pair of load bearing wall panels and a second pair of shear wall panels are installed. Then a third set of pallets including a service core for a third dwelling are mounted on the second pair of load bearing wall panels to form a ceiling for the second floor dwelling and the floor for a third dwelling. This procedure is repeated until all of the dwellings in the apartment are formed. Then prestressed concrete pallets are mounted on the uppermost load bearing wall panels to form the roof of the uppermost dwelling, and of the stack of dwellings. The interiors of the several dwellings are then grouted, and floor and wall coverings installed, whereupon the structure is ready for occupancy.

As will be appreciated by those skilled in the art, prestressed concrete pallets of the type employed in the practice of the present invention can be supported only at the two design load bearing points. In most instances, the blank pallets are handled by means of eyes cast in the concrete. However, the pallets upon which the service core is formed make this method of handling the pallets impractical. Accordingly, each service core is set in place by means of a pair of picking bars which extend under the support points of the beams of the pallet, a harness including members for connection to the opposite ends of the two picking bars, and a crane which operates through the harness and the picking bars to lift and position the pallet. On the other hand, both for fire prevention purposes and for the sake of appearance, it is highly desirable that the enclosure of each service core extend substantially into engagement with the pallet located next about the service core. To this end the enclosure of each service core is equipped with at least one picking bar slot positioned to permit withdrawal of one of the picking bars that will be used to install the service core or pallet above the service core. The picking bars used in the installation of the pallets weigh approximately 400 pounds. This necessitates reinforcing the picking bar slots to such an extent that the picking bar does not damage the service core as it is withdrawn.

The building codes of the various cities and states typically require a fire barrier having a one hour rating between adjacent dwellings in a multi-family dwelling. In the practice of the present invention this requirement is easily fulfilled with respect to pallets that do not comprise service cores by simply filling the spaces between the decks of the pallets and the load bearing wall panels and the shear wall panels with grouting. On the other hand, the enclosures of the service cores prevent access to these spaces and thereby prevent the filling of the spaces with grouting. For this reason the service cores are preferably installed with one edge of the deck engaged with the adjacent wall panel. At the other end of the deck a strip of sheet metal is secured between the enclosure and the deck. The strip of sheet metal is extended over the upper edge of the load bearing wall panels that supports the deck and is engaged by the load bearing wall panel that is mounted on the supporting panelto provide the necessary fire barrier.

In accordance with a particular embodiment of the invention, double loaded service cores are utilized in the construction of adjacent dwellings. That is, a single prestressed concrete pallet is equipped with two complete but separate sets of mechanicals, one for each of the adjacent dwellings. In such cases it is necessary to form a fire barrier having a one hour rating between the portion of the service core that is individual to one of the dwellings and the portion that is individual to the other dwelling.

The majority of the fire barrier for a double loaded core may comprise a wall including at least one layer of five-eights inch sheet rock. A pair of diverging sheet metal flanges are provided at the upper end of this wall for engagement with a beam of the pallet that is installed above the double loaded core to form the upper portion of the fire barrier. The fire barrier wall is also provided with a stub wall which is slidably supported at the end of the deck that will be engaged with a load bearing wall. During installation of the double loaded core the stub wall is retracted. Then, after the load bearing wall panels adjacent the double loaded core have been installed, the stub wall is moved outwardly and is engaged with the adjacent load bearing wall panel. By this means the fire barrier between the portions of the double loaded core that are individual to the separate dwellings is extended to the full height and the full width of the core.

In addition to the foregoing, the present invention incorporates numerous features which contribute greatly to its overall practicality. For example, notwithstanding the strength of prestressed concrete pallets, it has been found that a direct connection between a particular pallet and the enclosure of a service core situated beneath the pallet is not workable. Instead a slip joint is employed to provide a pleasing appearance while permitting relative movement between the pallet and the service core as a result of live loads.

Another important feature of the invention involves the manner in which convenience outlets are provided at spaced points around each dwelling. Thus, electrical conduits are formed in the load bearing wall panels when the panels are manuafactured. After the panels are installed, electric service lines are directed from the adjacent service cores through the conduits in the load bearing wall panels and along the shear wall panels. The shear wall panels are typically covered with wood panelling or the like, so that the resulting dwelling is equipped with suitable convenience outlets and yet has no exposed conduit or wiring.

Still another important feature of the invention involves an improved method of forming the enclosures of the service cores. It has been found that a great deal of time is wasted if the enclosures are formed by finishing the walls on one side, installing the walls on the pallet by fastening through the panel frame into the pallet, and then finishing the walls on the other side of the panel. In accordance with the present invention holes are formed in the pallets along the lines that will comprise the walls of the enclosures. This permits the walls to be completely finished and then secured to the pallets by means of lag screws which are inserted through the holes in the pallets from the bottom.

DESCRIPTION OF THE DRAWINGS A more complete understanding of the invention may be had by referring to the following Detailed Description when taken in conjunction with the accompanying Drawings, wherein:

FIGS. 1-7 are illustrations of progressive steps .in a method of fabricating dwelling units incorporating the invention;

FIGS. 8 and 9 are illustrations of presetressed concrete pallets utilized in the practice of the invention;

FIG. I is a view taken generally along the line l0l0 in FIG. in the direction of the arrows;

FIGS. 11 and 12 are perspective and end views, respectively, showing a method of and apparatus for installing service cores which is utilized in the practice of the invention;

FIG. 12A is an end view of an alternative type of prestressed concrete pallet that can be utilized in the practice of the invention;

FIG. 13 is an elevational view of an apartment complex constructed in accordance with the invention;

FIG. 14 is a plan view of the apartment complex shown in FIG. 13;

FIGS. l5Al5C are an enlarged plan view of one of the apartments comprising the apartment complex shown in FIG. 13;

FIG. 16 is an enlarged plan view illustrating the service core of one of the apartment buildings shown in FIG. 14;

FIG. 17 is a sectional view taken generally along the line l7-I7 in FIG. 16 in the direction of the arrows;

FIG. I8 is a sectional view taken generally along the line 18-18 in FIG. 16 in the direction of the arrows;

FIG. 19 is an enlargement of the upper portion of FIG. I8;

FIG. 20 is a sectional view taken generally along the line 20-20 in FIG. 16 in the direction of the arrows;

FIG. 21 is an illustration of special slots which are uti' lized in the practice of the invention to facilitate the installation of prestressed concrete pallets on previously erected load bearing walls;

FIG. 22 is a sectional view taken generally along the line 2222 in FIG. 14 in the direction of the arrows; FIG. 23 is an enlargement of a portion of FIG. 22;

FIG. 24 is a sectional view taken generally along the line 2424 in FIG. 14 in the direction of the arrows; FIG. 25 is an enlargement of a portion of FIG. 24;

DETAILED DESCRIPTION Method of Dwelling Construction Referring now to the Drawings, and particularly to FIGS. 1-7 thereof, a method of dwelling construction incorporating the present invention is employed to construct an apartment building 48. As is best shown in FIG. 1, the first step in the method comprises the erection ofa pair ofload bearing wall panels 50 and 52. The wall panels 50 and 52 are both. formed from prestressed concrete and are both nominally 6 inches thick. The wall panels 50 and 52 are further similar in that they are both provided with a plurality of slots or notches 54 formed in the upper ends and with a plurality of support members 56 which project inwardly from points adjacent their lower ends. The notches 54 are generally U-shaped, but comprise inwardly tapered side walls, and some of the notches 54' in the wall 50 extend only part way through the wall so as to provide a flush outer surface. The supporting members 56 may comprise any convenient construction, butpreferably comprise pipe stubs cast into the panels 50 and 52 and extending inwardly therefrom. One difference between the wall panels 50 and 52 is that the wall panel 50 is provided with a door opening 58.

Referring now to FIG. 2, the next step in the method of dwelling construction comprises the installation of a service core 60. The service core 60 comprises a prestressed concrete pallet 62 and. an enclosure 64 formed on the pallet 62. The service core 60 further comprises complete mechanicals for a dwelling unit, i.e., complete kitchen facilities, complete bathroom facilities, and complete temperature control facilities.

The prestressed concrete pallet 62 of the service core 60 is shown in FIG. 8. The pallet 62 comprises a deck 66 and three beams 68 which depend from the deck 66. Thus, the pallet 62 is of the type commonly known as a triple T deck. A plurality of tension members extend through each beam 68 of the pallet 62 and serve to prestress the beams, whereby the beams 68 are adapted for support at spaced points indicated by the arrows 72 to support a load on the deck 66. As is well known in the art, a prestressed concrete pallet of the type shown in FIG. 8 is subject to breakage unless it is properly supported.

The cross sectional configuration of the pallet 62 is shown in FIG. I2. Those skilled in the art will appreciate the fact that the invention may also be practiced using either solid core or hollow core prestressed concrete pallets 62' of the type shown in FIG. 12A. The pallet 62 comprises a deck 66' and a plurality of beams 68' which depend from the deck 66' between cylindrical passageways 69. A plurality of tension members 70 extend through a lower portion 71 One difference between the pallet 62 and the pallet 62' is that whereas the beams 68 of the pallet 62 are exposed, the bottom of the pallet 62 is flat.

Referring again to FIG. 2, the enclosure 64 of the ser' vice core 60 is formed on the deck 66 of the prestressed concrete pallet 62. The enclosure 64 is preferably formed from materials of the type used in constructing conventional homes and similar buildings, i.e., two by four and two by six studs, drywall panels, and similar materials. The enclosure 64 includes interior partitions which separate the various mechanicals of the dwelling unit into kitchens, bathrooms, and the like, and further includes at least one end wall and a dropped or false ceiling 76.

In accordance with the illustrated embodiment of the invention, the service core 60 is completely fabricated at a factory by means of mass production techniques. The fabrication of the core 60 comprises construction of the walls, partitions, and ceilings in suitable jigs and fixtures, installation of the walls, partitions, and ceilings, installation of all mechanicals, installation of electrical, plumbing, and heating/air conditioning risers for the mechanicals, installation of all doors and cabinetry, installation of floor and wall coverings, and painting. Thus, when the service core 60 is installed between the load bearing wall panels 50 and 52, it is complete and ready for use. this feature of the invention is highly advantageous in that it not only reduces the cost of a building 48 by truck. During such transportationQthe service core 60 is supported solely at points corresponding to the support points of the beams. This is accomplished by means of members positioned under the support points of the beams to maintain the remainder of the pallet out of contact with the bed,'etc. ofthe truck.

The service core 60 is installed by means of apparatus of the type shown in FIGS. 11' and 12. A pair of picking bars 78 are positioned under the beams 68 of the pallet 62 at points corresponding to the support points of the beams. The picking bars 78 areengaged by a harness 80 comprising a plurality of cables 82 and a spreader frame 84 which functions to cause the cables 82 to extend vertically upward from the picking bars 78 to points above the enclosure 64 of the service core 60. The cables 82 are connected to a beam 86 which is in turn supported by a cable 88 extending from a crane (not shown). By this means the crane functions through the harness 80 and the picking bars 78 to lift and position the service core 60.

Referring again to FIG. 2, the service core 60 is installed between the load bearing wall panels 50 and 52 with each beam 68 of the pallet 62 engaged with one of the support members 56. It will be appreciated that due to manufacturing tolerances and in order to facilitate the installation of the core 60 between the wall panels 50 and 52, the length of the pallet 62 is necessarily somewhat less than the distance between the interior surfaces of the walls. The resulting gap is accommodated by positioning the deck 66 closely in engage- Y ment with the wall panel 50, whereupon a suitable entry in the enclosure 64 is aligned with the door opening 58 in the wall panel 50. This forms a small gap between the deck 66 and the wall panel 52. However, an

end wall is provided at the end of the enclosure 64 remote from the door opening 58, whereby the gap is not visible from within the service core 60. a

The next step in the method of dwelling construction comprises the installation of a pair of blank prestressed concrete pallets 90 between the load bearing wall panels 50 and 52. The pallets 90 are handled by means-of cables 92 which are connected to eyes 93 inthe pallets.u The same procedure could be employed in handling service cores except that the enclosures of the service cores prevent access to the eyes of the pallets. Thus, the service cores must be handled by means of picking bars The blank-pallets 90 are identical to the pallet 62 of the servicecore in that they each comprise a deck, three beams depending from the deck, and tension members extending through the beams for prestressing the pallets. The pallets are positioned between the wall panels 50 and 52 with their respective beams engaged with the support members 56 of the walls. The decks of the pallets 90 are therefore aligned with the decks 66 of the pallet 62, whereby the pallets 90 cooperate:with the pallet 62 to form the floor of a dwelling unit.

- As is best shown-in FIG. 4, the installation of the pallets 90 is followed by the installation of a pair of shear wall panels 94 and 96. The wall panels 94 and 96 are formed from prestressed concrete, but differ from the load bearing wall panels 50 and 52 in that they are nominally 4 inches thick. The shear wall panels include window openings 98 and a door opening 100 and serve the dual functions of enclosing the ends of the dwelling unit and maintaining the load bearing walls erect.

The shear wall panels 94 and 96 are preferably connected to'the loadbearing wall panels 50 and 52 by forming welds between suitable members which either comprise part of or are connected to the reinforcing structure of the wall panels. The-load bearing wall panels and the shear wall panels may also be joined by other techniques of the type commonly employed in the construction industry to connect prestressed concrete structural members. The various prestressed concrete pallets which are employed in the practice of the inventionmay be connected to the load bearing wall panels by similar techniques, however, it has been found that it is often unnecessary to connect the pallets to the load bearing wall panels in any fashion.

Upon the installation of the shear wall panels 94 and 96, the lowermost'apartment of the apartment building 48 is structurally complete. Thereafter, a service core 102 for a second dwelling unit is mounted on the load bearing wall panels 50 and 52. As is shown in FIG. 5, the service core 102 comprises a prestressed concrete pallet 104 and an enclosure 106 formed on the pallet 104. The service core 102 further comprises complete mechanicals for the second: apartment.

The-pallet 104 of the service core 102 is illustrated in FIG. 9. The pallet 104 is similar to the pallet 62 in that it comprises a deck 108 and three beams 110 which depend from the deck. A plurality of tension members 112 extend through the beams 110 to prestress the beams and thereby adapt the beams for support at spaced points indicated by the arrows 114 to support a load on the deck 108.

The pallet 104 also differs from the pallet 62 in several important respects. First,the deck 108 is discontinued at spaced points 116 corresponding to the positioning of the load bearing wall panels 50 and 52. Second,.the deck 108-and the beams 110 extend beyond one of the support points 114 to form a cantilever portion 118 of the pallet 108. At least some of the tension members 112 extend through plastic tubes 120 or are otherwise disengaged from the-material of the beams 110 in the Cantilever portion 118. This is necessary in order that the portion 118 can be supported in cantilever fashion.) 

1. The dwelling unit comprising: a pair of spaced load bearing wall panels; a pair of prestressed concrete pallets extending between and supported by the load bearing wall panels; one of said pallets bearing substantially the entire kitchen, bathroom and temperature control facilities for the dwelling unit; the other of said pallets being positioned adjacent said one of the pallets such that the pair of pallets forms the floor of the dwelling unit; shear control means for preventing movement of the load bearing wall panels in a direction transversely of the load bearing wall panels; and ceiling means supported by the load bearing wall panels and forming the ceiling of the dwelling unit.
 2. The dwelling unit of claim 1 further characterized by: a third pallet disposed adjacent said one of said pallets to further define the floor of the dwelling unit.
 3. The dwelling unit of claim 1 wherein: the ceiling means comprises a second pair of prestressed concrete pallets.
 4. The dwelling unit of claim 3 wherein: said one of said pallets includes interior walls defining at least one living compartment and a false ceiling supported by the interior walls for at least one said living compartment.
 5. The dwelling unit according to claim 1 further comprising: a second pair of spaced load bearing wall panels positioned on and supported by the first pair of load bearing wall panels; a second pair of prestressed concrete pallets extending between and supported solely by the first pair of load bearing wall panels; one pallet of the second pair bearing the entire kitchen, bathrooM, and temperature control facilities for a second dwelling unit; the other pallet of the second pair being positioned adjacent to said first pallet of the second pair for cooperation therewith to form the floor of the second dwelling unit, and wherein the shear control means also prevents movement of the second pair of load bearing wall panels in a direction transversely of the load bearing wall panels.
 6. The dwelling unit according to claim 5 further comprising: a third pair of prestressed concrete pallets extending between and supported solely by the second pair of load bearing wall panels and forming a ceiling for the second dwelling unit.
 7. A dwelling unit comprising: a concrete pallet including a deck, a plurality of longitudinally extending prestressed concrete beams each depending from the deck, and tension members extending through the beams for prestressing the pallet such that the beams are adapted for support only at or near spaced optimum load support points to support a load on the deck; a pair of load bearing walls positioned to support said pallet at longitudinally spaced points on the beams depending from the deck to define a habitable area therebetween; enclosure means formed on the pallet flush with the deck including complete mechanicals for the dwelling unit, said pallet and said enclosure means forming a moveable unit for positioning said pair of load bearing walls; a second prestressed concrete pallet having at least one depending prestressed concrete beam with spaced optimum load support points, said beam being supported on the load bearing walls at said optimum load support points to define the ceiling of the unit; and means for maintaining the load bearing walls erect.
 8. The motel unit according to claim 7 wherein the means for maintaining the load bearing walls erect comprises a wall extending longitudinally of the pallet and interconnecting the load bearing walls.
 9. The motel unit according to claim 8 wherein the longitudinally extending wall is positioned at one edge of the pallet and is finished on both sides to define one wall of the motel units and the opposite wall of an adjacent motel unit.
 10. The motel unit according to claim 9 wherein the pallet extends beyond the load bearing walls at both ends to define an entryway at one end of the unit and a balcony at the other end.
 11. The dwelling unit comprising: at least one concrete pallet including a deck portion having a substantially planar upper surface, at least one beam portion depending from the deck portion, and tension members enclosed in the beam portion for prestressing the beam portion such that the beam portion is adapted for support at a pair of spaced points to support a load on the deck portion; enclosure means formed on the pallet and comprising complete kitchen, bathroom and temperature control means for the dwelling unit; a pair of load bearing wall means positioned in engagement with the spaced points of the beam portion to support the pallet and the enclosure means thereon; shear control means for maintaining the load bearing wall means erect; an additional concrete pallet including a deck portion having a substantially planar upper surface, at least one beam portion depending from the deck portion, and tension members enclosed in the beam portion for prestressing the beam portion such that the beam portion is adapted for support at spaced points to support a load on the deck portion, and wherein the load bearing wall means supports the additional pallet adjacent the first pallet for cooperation therewith to form the floor of the dwelling unit; and ceiling means formed by a plurality of concrete pallets each including a generally planar deck portion having at least one beam portion depending from the deck portion and tension members enclosed in the beam portion for prestressing the beam portion such that the beam portion is adapted for support at spaced points to support a load on the deck portion, the concrete pallets of the ceiling means being supported by the load bearing wall means.
 12. The multi-family dwelling unit comprising: a pair of substantially vertically extending load bearing walls; a first substantially planar deck extending horizontally between the load bearing walls and supported thereby; enclosure means formed on the deck and including complete mechanicals for two dwelling units, including a fire barrier extending substantially the entire length of the deck between the two sets of mechanicals; at least second and third decks supported by the load bearing walls and positioned adjacent to the deck bearing the enclosure means for cooperation therewith to define the floor of the two dwelling units; additional decks supported above the first, second and third decks comprising the floor of the two dwelling units to form the ceiling of the two dwellings units; and cooperating means on the fire barrier and on one of the first, second and third decks for extending the fire barrier the entire distance between the floor and the ceiling of the two dwelling units.
 13. The multi-family dwelling unit comprising: at least three substantially planar, horizontally extending decks positioned adjacent one another to define the floors of adjacent dwelling units; enclosure means formed entirely on the center deck and including complete kitchen, bathroom and temperature control facilities for two dwelling units; each of the decks comprising a prestressed concrete pallet including a substantially planar deck, at least one beam formed integrally with and depending from the deck, and tension members extending through the beam to prestress the pallet and thereby adapt the beam to support a load on the deck; load bearing walls mounted at the ends of the pallets; and at least three additional prestressed concrete pallets supported on the load bearing walls to define the ceilings of the adjacent dwelling units.
 14. The dwelling unit comprising: at least one concrete pallet including a deck portion having a substantially planar upper surface, a plurality of prestressed concrete beam portions depending from the deck portion, and tension members enclosed in the beam portions for prestressing the beam portions such that the beam portions are adapted for support only at or near spaced optimum support points to support a load on the deck portion; enclosure means formed flush with the deck portion of the pallet, so that the deck portion forms a floor for the enclosure means; and a pair of vertically extending load bearing walls having notches formed in their upper ends for receiving the beam portions of the pallet and for engagement with the optimum support points of the beam portions to support the pallet and the enclosure means thereon, whereby said enclosure means and said pallet are assembled and placed as a unit on said load bearing walls, said beam portions of the pallet including cantilever portions extending beyond one of said load bearing walls and said deck portion of the pallet including a primary portion positioned between the load bearing walls and a secondary portion positioned outside the load bearing walls on the cantilever portions of the beam portions.
 15. The multi-family dwelling unit comprising: a pair of substantially vertically extending load bearing walls; a substantially planar deck extending horizontally between the load bearing walls and supported thereby; enclosure means for forming an enclosure on the deck, said deck forming a floor for the enclosure, said enclosure means including two complete sets of mechanicals, one for each of two dwelling units, said deck and said enclosure means being assembled and placed as a unit on said load bearing walls, said enclosure means including a fire barrier extending substantially the entire length of the deck between said two sets of mechanicals; and at least two additional decks supporTed by the load bearing walls and positioned on either side of the deck bearing the enclosure means for cooperation therewith to define the floor of the dwelling units.
 16. The dwelling unit comprising: a prestressed concrete pallet including a relatively thin deck, a plurality of prestressed concrete beams formed integrally with and depending from the deck, and tension members extending through the beams for prestressing the pallet and thereby adapting the beams for support only at or near spaced optimum load support points to support a load on the deck; enclosure means for forming an enclosure on the deck, said deck forming a floor for the enclosure, and including vertically extending walls situated at the periphery of the deck, a ceiling extending over the deck and between the walls, and at least one partition situated within the walls and beneath the ceiling; complete kitchen, bathroom, and temperature control facilities mounted on the deck within the enclosure means; load bearing wall panels having means for engaging the beams at the optimum load support points to support the pallet and thereby support the enclosure means and the kitchen, bathroom and temperature control facilities within the enclosure means, whereby said enclosure means and said pallet are assembled and placed as a unit on said load bearing wall means; and a second prestressed concrete pallet having at least one depending prestressed concrete beam with spaced optimum load support points, said beam being supported on the load bearing wall means above the enclosure means on the first pallet, enclosure means mounted on the second pallet, and complete kitchen facilities, bathroom facilities, and temperature control facilities for a second dwelling unit supported on the second pallet within the enclosure means thereon. 